The Mediterranean region is predicted to be highly impacted by climate change and the availability of water resources is expected to decrease. This study aims to assess the potential impact of climate change in an aquifer located in Northeastern Greece, for the period 2041-2070. For this, climate data from three Regional Climate Models (RCMs) were bias-corrected using the Cumulative Distribution Function (CDF) method, based on historical data for the period 1981-2000. The bias-corrected data are fed to the SWAT model, in order to calculate monthly groundwater recharge values, which were then inputted to the MODFLOW model to predict future groundwater level distribution. The performance of the CDF correction method was assessed. The results indicate a significant increase in both maximum and minimum temperature and decrease in precipitation. In addition, groundwater recharge was found to decrease and groundwater abstractions to increase, leading to a subsequent decrease in groundwater level.